In the most simple versions, a foot gauge comprises a plate on which the user places a foot, the foot bearing firstly against a first abutment extending transversely for the heel and secondly against a second abutment extending longitudinally for the inside of the foot. The plate carries a graduated scale enabling the user to see the size of the foot from indications that are immediately visible on the graduated scale beyond the portion of the scale that is hidden by the presence of the foot.
In that version, the graduated scale has a longitudinal disposition, and the size corresponds strictly to the length of the foot.
In a more elaborate version, known from document FR 2 763 221, the particular disposition of the graduated scale enables size to be measured in a way that takes account both of the length of the foot and of its width.
Nevertheless, such a gauge lacks precision, insofar as the size value read by the operator can for any one foot vary as a function of the position of the operator relative to the plate, since in order to ensure that an exact measurement is taken the operator must take up a position that is strictly vertical above the support plate.
To mitigate that drawback, proposals have been made to fit a foot gauge with a moving assembly including a transversely-extending abutment for coming into contact with the longest toe, like a height gauge for measuring a user's height.
In a more elaborate version, the foot gauge has a moving assembly comprising not only a transverse abutment as described above, but also a longitudinal abutment for coming into contact with the outside of the foot, together with means for identifying size. One such gauge is described in document FR 2 233 955.
In that document, the gauge has means for measuring the length of the foot and means for measuring the width of the foot, said means being mechanically or electrically connected to a foot-size indicator in which the size that is specified depends both on the length and on the width of the foot.
In document FR 2 233 955, once the foot has been pressed against the support plate, the operator performs two distinct operations to cause firstly the transverse abutment to slide into contact with the longest toe, and secondly the longitudinal abutment to slide to come into contact with the outside face of the foot.